Prepare Sushi Rice:
Rinse sushi rice until the water runs clear. Cook the rice, and while it's still warm, mix it with sushi vinegar. Let it cool to room temperature.
Slice your chosen fish and vegetables into thin strips or julienne.
Set Up Your Workstation:
Place the bamboo mat on a clean surface, cover it with plastic wrap, and have a bowl of water with a bit of rice vinegar nearby to moisten your hands.
Place Nori on the Mat:
Lay a sheet of nori, shiny side down, on the bamboo mat.
Spread Rice on Nori:
Wet your hands and spread a thin layer of sushi rice over the nori, leaving a small margin at the top.
Add Fillings and Roll:
Place your chosen fillings in the center of the rice. Lift the edge of the bamboo mat closest to you, and roll it over the fillings, pressing gently. Continue rolling until you reach the exposed margin. Wet the margin with water and seal the roll.
Slice and Serve:
Use a sharp, wet knife to slice the roll into bite-sized pieces. Arrange on a plate and serve with soy sauce, wasabi, and pickled ginger.